Plier-type tool having cam and slot actuation means



a rch 14, 1967 SHICHIRO SATO PLIER-TYPE TOOL HAVING CAM AND SLOT ACTUATION MEANS 5 Sheets-Sheet 1 Original Filed March 11, 1964 Mm/en UUQIUTO P March 14, 1967 SHICHIRO SATO PLIERTYPE TOOL HAVING CAM AND SLOT ACTUATION MEANS Original Filed March 11, 1964 5 Sheets-Sheet 2 March 14, 1967 SHICHIRO SATO PLIER-TYPE TOOL HAVING CAM AND SLOT ACTUATION MEANS 5 Sheets-Sheet 3 Original Filed March 11, 1964 l l \\N 6 I\ F/ANHI H 0 n o n a w t 0.11 0 m c O M 5 March 14, 1967 SHICHIRO SATO PLIER-TYPE TOOL HAVING CAM AND SLOT ACTUATION MEANS- 5 Sheets-Sheet 4 Original Filed March 11, 1964 March 14, 1967 SHICHIRO SATO PLIER-TYPE TOOL HAVING CAM AND SLOT ACTUATION MEANS 5 Sheets-Sheet 5 Original Filed March 11, 1964 lxl/enor \i high L'm United States Patent Gfitice 33%,692 Patented Mar. 14, 1967 3,308,692 PLIER-TYPE TOOL HAVING CAM AND SLOT ACTUATION MEANS Shichiro Sato, 14 of 172, Shimo-oh-ichi Higashicho, Nishinomiya, Japan Continuation of application Ser. No. 351,185, Mar. 11, 1964. This application Apr. 13, 1966, Ser. No. 542,996 Claims priority, application Japan, Mar. 18, 1963 (utility model), 38/ 19,360 1 Claim. (Cl. 81-342) This application is a continuation of my application Ser. No. 351,185, now abandoned.

This invention relates to new and useful improvements in pliers or plier-type tools in which a pair of jaw members are adapted to engage work pieces.

For many uses, plier-type tools of this general character require a strong grip of the jaws upon the work piece in order that slippage may not take place. It is also re quired for crimping o-r severing heavy work pieces such as electrical connectors. This result is obtainable, of course, :by providing the handle with a relatively long leverage, but this provides a disadvantage in the fact that the length of the movement at the ends of the handle arms increases proportionately to the length of the arms from the pivot point, the general result being that in operating such tools the operator is required to utilize both hands in order to obtain the proper pressure at the jaws. While attempts have been made to meet this condition by articulate-d levers etc., the results have not been satisfactory in many cases.

It is among the objects of the invention to provide a plier-type tool having a large mechanical advantage with a relatively short leverage and capable of ready manipulation by one hand.

Another object of the invention is to provide a pliertype tool which is simple and efiicient in operation, durable in construction and which can be manufactured at a relatively low cost.

A further object of the invention is to provide a pliertype tool which is available for two or more kinds of work pieces having different diameters.

The plier-type tool according to the invention comprises a stationary member, a movable jaw member and a drive handle lever. The stationary member consists of a jaw portion and a handle portion on the opposite sides with respect to a pivot. Through this pivot the movable jaw members is pivot-ally connected to the stationary member so as to cooperate with the jaw portion thereof. The drive handle lever is .pivotally connected through another pivot to the stationary member so as to cooperate with the handle portion thereof. The drive handle lever is also connected through slidably connecting means preferably, a pin-slot mechanism to the movable jaw member so that the movable jaw member is operated against the jaw portion of the stationary member when the drive handle lever is operated against the handle portion of the stationary member. The invention is characterized in that in such a plier-type tool as above the pivot of the movable jaw member to the stationary member and the above mentioned slidably connecting means are disposed on the opposite sides with respect to the pivot of the drive handle lever to the stationary member.

Since the plier-type tool according to the invention is thus constructed in a double step lever mechanism, relatively high gripping or shearing pressure on the jaw members can be obtained with a relatively short length of the handles. In addition to this, the special disposition of the connecting points of the component members to each other enables the whole length of the tool to be shortened to a great extent.

Other objects of the present invention will be apparent from the following disclosure thereof, as set forth wherein:

FIGURE 1 is a front view of pliers embodying the present invention, showing the complete pliers with the jaw members fully closed;

FIGURE 2 is a back view of the same showing the jaw members fully opened;

FIGURE 3 is a left side View of FIGURE 1;

FIGURE 4 is a right side view of FIGURE 1;

FIGURE 5 is a longitudinally sectional view of the pliers taken along the line 5-5;

FIGURE 6 is another sectional view of the pliers taken along the line 6-6 of FIGURE 3;

FIGURE 7 is a front view of the stationary member and the drive handle lever, pivotally connected to each other, of the pliers illustrated in FIGURES 1 to 6;

FIGURE 8 is a side view of FIGURE 7;

FIGURE 9 is a back view of the movable jaw member of the pliers illustrated in FIGURES 1 to 6;

FIGURE 10 is a side view of FIGURE 9;

FIGURE 11 is a front view of a plier-type tool showing another embodiment of the invention;

FIGURE 12 is a back view of the same;

FIGURE 13 is a left side view of FIGURE 11;

FIGURE 14 is right side view of FIGURE 11;

FIGURE 15 is a longitudinally sectional view of the plier-type tool taken along the line 15-15 of FIGURE 11' of typical embodiments in the accompanying drawings,

FIGURE 16 is a sectional view taken along the line 16-16 of FIGURE 13;

FIGURE 17 is another front vie-w of the plier-type tool with the jaw members fully closed, showing that the tool is available for a work piece having a larger diameter;

FIGURE 18 is a back view of FIGURE 17; and

FIGURE 19 is a further front view of the plier-type tool showing the state during which the pivoting point of the drive handle lever to the stationary member is being changed over to each other point.

Referring now to the accompanying drawings in detail, the pliers according to the invention as shown in FIG- URES 1 to 10 comprises three component members: a stationary member 21, a movable jaw member 22 and a drive handle lever 23.v

The stationary member 21 is in the form of an elongated lever consisting of a jaw portion 24 and a handle portion on the opposite sides with respect to a pivot 26. Through this pivot 26 the movable jaw member 22 is pivotally connected to the stationary member 21 so as to cooperate with its jaw portion 24. The pivot 26 may be a rivet and pass through the respective pivot openings 27 and 28 of the members 21 and 22 (FIGURE 5). This pivot may be fixed to one of the members 21 and 22. The jaw member 22 is movable from an open position to a fully closed position against the stationary jaw 24, pivoting about the pivot 26. The jaw members 22 and 24 are provided at the front with usual serrations 29 and 30 for gripping purposes and usual cutting edges 31 and 32.

The drive handle lever 23 is pivotally connected through a pivot 33 to the stationary member 21 so as to cooperate with its handle portion 25.

This pivot 33 may be a pin fixed to the handle lever 23. 34 indicates the pivot openings in the stationary member 21 for pivotally carrying the pin 31.

The drive handle lever 23 is also pivotally connected through a slidably connecting mechanism generally indicated as 34 to the movable jaw member 22. Preferably, the slidably connecting mechanism 35 comprises a pin on one member and a slot in the other member. For example a pin 36 fixed on the movable jaw member at its rear extension across the pivot 26 engages with a slot 37 formed in the drive handle lever 23. The pin 36 may be a roller rotatably carried. The mechanism may be reversed. The slot 37 has a length in the direction toward the pivot 26 so as to permit the pin 36 to slide in this direction. In this manner, the movable jaw member 22 can be operated against the stationary handle member 23, while permitting the pin 36 to slide along the slot 37, and the movable jaw member 22 and the drive handle member 23 pivoting about the respective pivots 26 and 33.

According to the invention, as one of the most important features, the pivot 26 of the movable jaw member 22 and the connecting pin 36 between the movable jaw member 22 and the drive handle lever 23 are disposed on the opposite sides with respect to the pivot 33 of the drive handle lever 23. Preferably, these three connecting points 26, 33 and 36 are substantially aligned in the direction of the length of the pliers when the pliers is in the middle open position.

Since the plier according to the invention is constructed in a double step lever mechanism, relatively high gripping or shearing pressure on the jaw members 22 and 24 can be obtained with a relatively short length of the handles 23 and 25. In addition to this, the special disposition of the connecting points of the component members 21, 22 and 23 to each other as defined in the above enables the whole length of the pliers to be shortened to such a great extent comparable to usual pliers. This short leverage construction enables the pliers to be manipulated by one hand.

It should be noted that it is also possible to construct the pliers according to the invention in such a manner that the drive handle lever 23 is pivotally connected through a pin slot mechanism to the stationary member 21 while the movable jaw member is pivotally connected through a fixed pin to the drive handle lever.

Preferably, the connecting end portion of the drive handle lever 23 is carried between the rear end portion of the movable jaw member 22 and the stationary member 21, two connecting pivot pins 33 and 36 being disposed on the opposite surfaces thereof. In this manner, the pliers can be constructed in such a compact and decent looking form as shown in figures.

Another embodiment of the present invention is shown in FIGURES 11 to 19. The tool illustrated therein is available for two or more kinds of work pieces having different diameters. The tool comprises a stationary member 51, a movable jaw member 52 and a drive handle lever 53. The stationary member 51 consists of a jaw portion 54 and a handle portion 55 on the opposite sides with respect to a pivot 56. Through this pivot 56 the movable jaw member 52 is pivotally connected to the stationary member 51 so as to cooperate with the jaw portion 52. The jaw members 52 and 54 are provided with two different kinds of usual serrations 57, 58 and 59, 60. The drive handle lever 53 is pivotally connected through a pivot pin 61 to the stationary member 51 so that the handle lever 53 cooperates with the handle portion 55 of the stationary member 51 and is movable against the latter, pivoting about the pivot pin 61. The pivot pin 61 may be fixed the drive handle lever 53 at its top end. The stationary member 51 is provided with a plurality of, for example, three pivot openings 62, 63 and 64 which are communicated by connecting passages 65 and 66 to each other. The pivot pin 61 may be shaped in a partly square and partly circular section as shown in FIGURE 12, while the three pivot openings in the stationary member 51 may be shaped substantially in a circular section so as to pivotally retain the pivot pin 62. The connecting passages 65 and 66 may have a width narrower than the diameter of the circular portion of the pivot pin 61 and substantially equal to the width of the squared portion of the pivot pin 61. The drive handle lever 53 is, therefore, movable from an open position to a closed position against the stationary handle 55, pivoting on the axis of the pivot pin 61 carried by any of pivot openings 62, 63 and 64. The pivot pin 61 may be changed over from one to any others of three pivot openings through the connecting passages 65 and 66 when the connecting passages 65 and 66 become aligned with the direction substantially right to the width of the squared portion of the pivot pin 61 as shown in FIGURE 19. The efliect of the change-over of the pivoting point of the pivot pin 61 will be described in detail hereinafter. It should be noted that the above connecting mechanism between the stationary member 51 and the drive handle lever 53 may be reversed by interchanging the pin 61 and the pivot openings 62, 63 and 64.

The drive handle lever 53 is pivotally connected through a slidably connecting mechanism generally indicated as 67 to the movable jaw member 52. The connecting mechanism 67 may consist of a pin 68 fixed on the drive handle lever 53 and a slot 69 formed in the movable jaw member 52. This mechanism may be reserved. The slot 69 may have a length in the direction toward the pivot 56 so as to permit the pin 68 to slide in this direction. In this manner, the movable jaw member 52 can be operated against the stationary jaw member 54 when the drive handle lever 53 is operated against the stationary handle 55, while permitting the pin 68 to slide along the slot 69, and the movable jaw member 52 and the drive handle lever 53 pivoting about the respective pivots 56 and 68. It will be seen that the slot 69 is formed in a longer size than the slot 37 of the pliers illustrated in FIGURES 1 to 10. This is required in order that the movable jaw member 52 may be operated by the drive handle lever 53 with any position of the pivot pin 61 to be pivotally carried.

With the tool illustraed in FIGURES 11 to 19 there is obtained a large mechanical advantage and a short leverage construction as well as in the pliers illustrated in FIGURES 1 to 9. In addition to this, the tool of this embodiment has another great advantage that the tool is available for two or more kinds of work pieces having different diameters. When the pivot 61 is positioned in the pivot opening 62 as shown in FIGURE 12, the tool is adapted to grip work pieces of the relatively small diameter, while when the pivot 61 is positioned in any of other pivot openings 63 and 64, the tool may be used for gripping work pieces of relatively large diameters. The pivot opening 63 is for a larger diameter and the pivot opening 64 is for the largest diameter. Solid and dotted lines in FIGURES 1'7 and 18 show a fully closed position and an open position of the jaw members 52 and 54, respectively, where the pivot 61 is pivotally carried by the pivot opening 64 for the largest diameter use. It would be understood that the jaw members 52 and 54 has still a certain spread at their fully closed position. In this manner, a relatively large work piece can be grappled.

The tool of this type is operable with one hand from an open position to a closed position with each position of the pivot 61 to be pivotally carried, whereby the jaw members 52 and 54 are closed and open.

While in the foregoing there have been disclosed the preferred embodiments of the invention, other various modifications may become apparent to those skilled in the art to which the invention relates. Accordingly it is not desired to limit the invention to this disclosure and other various modifications may be resorted to, such as may fall within the spirit and scope of the appended claims.

What I claim is:

A tool comprising an elongated member adapted to remain stationary with respect to other components of the tool, said elongated stationary member having a jaw portion at one end and an elongated handle portion situated beyond said jaw portion and extending to the other end of said elongated stationary member, first pivot means connected with said elongated stationary member between said jaw and handle portion thereof, a movable jaw memher pivotally connected by said first pivot means to said stationary member for cooperation with said jaw portion thereof, second pivot means operatively connected with said stationary member and situated between said first pivot means and said handle portion of said stationary member adjacent to said first pivot means, a drive handle lever pivotally connected at one end portion by said second pivot means to said elongated stationary member and said drive handle lever extending beside said handle portion to cooperate therewith during turning of said lever with respect to said stationary member at said second pivot means, and pin-and-slot means interconnecting said lever with said movable jaw member for turning the latter at said first pivot means with respect to said jaw portion of said stationary member during turning of said lever with respect to said stationary member at said second pivot means, said pin-and-slot means including an elongated slot extending generally longitudinally of said stationary member and said lever, having one end situated adjacent said second pivot means and extending from said latter one end thereof away from said second pivot means toward the ends of said stationary member and lever which are on the side of said second pivot means opposite from said first pivot means, said lever being turnable at said second pivot means with respect to said stationary member between a fully closed position where said movable jaw member engages said jaw portion of said stationary member and a fully opened position where said movable jaw member is situated at a maximum distance from said jaw portion of said stationary member, and said lever having an intermediate position between said fully opened and fully closed positions, said first pivot means, said second pivot means, and a pin of said pin-andslot means all being located substantially in alignment with each other and distributed substantially longitudinally of said lever and stationary member in said intermediate position of said lever, said second pivot means including a pivot pin integrally fixed with and projecting a predetermined position said pin of said second pivot dimension aligned with said narrow portions to be movable therethrough for situating References Cited by the Examiner UNITED STATES PATENTS 512,451 1/1894 Schultz 25O 615,956 12/1898 Broadbooks 30188 1,915,404 6/1933 Clifton 8166 X 2,464,145 3/1949 Mead 81-365 FOREIGN PATENTS 1,030,095 5/ 1958 Germany.

WILLIAM FELD'MAN, Primary Examiner. MILTON S. MEHR, Examiner. 

